Apparatus for chlorinating solutions



Dec; 7, 1926 1,609,757

J. H. M MAHON APPARATUS FOR CHLORINATING SOLUTIONS Original Filed Jan. 23, 1924 Z Agra/52ml:

@g M M am ATTORNEYS Patented Dec- 7, 1926. I

UNITED STATES PAT JAMES H. MAOMAHON, OF NIAGARA FALLS, NEW YORK;'ASSIGNOB TO THE IATEIIESON OFFICE.

ALKALI WORKS, INC., 01 NEW YOTtK, N. Y., A CORPORATION OF vmemm.

AIPARATUS FOR CHLORINATING SOLUTIONS.

Original application filed January 23,1924, Serial No. 688,027. Divided and this app l ieat1on filed December a, 1924;

This invention relates to im rovements' in the preparation of liquid b each solutions. More particularly, the present invention relates to an improved apparatus for making liquid bleach solutions from milk of lime or other alkaline solutions and liquid' liquid chlorine from the chlorine container discharged while still in a liquid state, or while still a considerable part of the liquid -chlorine remains liquid, directly into the milk of limeor other alkaline solution to be chlorinated. The alkaline solution, into which the liquid chlorine is directly introduced, is vigorously agitated to bring about rapid dissemination of the chlorine throughout the alkaline liquor or solution.

When liquid chlorine, which is maintained in e chlorine container under a high pressure, is passed through a pressure reducing valve, some of the chlorine is, vaporized because of the reduction in ressure, but a considerable part of the c orine' is cooled and remains in a liquid state at .a much lower temperature approximating its boiling point at atmospheric pressure or at the pre's sure to which the chlorine isreduced by the reducing valve. By introducing the d110- rine after expansion directly into the milk of lime or other alkaline solution to be chlorinated, the cooling effect due to the expansion as well as the cooling efiect'due to the low temperature of liquid chlorine, is transmitted to the solution and serues to neutralize toan important extent the heat of the reaction between the chlorine and the milk of Iime. The cooling effect, accordingly, will be exerted upon the milk of l me solution at the point at which the chlorine is introduced therein and'gtimately admixed therewith. In my prior Patent No. 1,426,752 granted August 22, 1922, I haved'escribed" and claimed a method. and apparatus for the pro duction of liquid bleach solutions wherein the liquid chlorine is conducted eitherdirect- .ly into the alkaline solution or first into heat interchanging relation therewith and; then into the alkaline solution. .Whenthe liquid Serial No. 754,526.,

chlorine is passed through a coil submerged in the milk of lime solution, the chlorme.

is vaporized to the extent that the heating ef- .fect of the milk of lime solution overcomes or neutralizes the heat of vaporization, so that the cooling efl'ect of the vaporization of the chlorine is exerted upon the body of the milk of lime which comes in contact with the \vaporizing coil. When, however, the

chlorine is introduced directly into the milk of lime solution, the cooling effect is exerted for the most part at the point at which the chlorine is introduced into the solution and at the oint at which it reacts with the solution. ince the reaction of chlorine with milk of lime or other alkaline solutions gives off considerable heat, the direct introduction of the liquid chlorine into the milk of lime has the advantage that it makes the cooling effect of the liquid chlorine available at the point or at approximately the point where the heat of reaction is generated. The cooling eflect is therefore localized as well as the heat of reaction, and these tend to neutralize each other in a localized area or' in the approximate location where the I other alkaline solution to be chlorinated will be at alower pressure than that of the liquid chlorine in'its container; and, in such cases, the chlorine will be passed through a reducing valve or" equivalent device'to reduce the hlorine to approximately the pressure of the solution to be chlorinated before it is fadmixed therewith. Since .the liquid chlorine in its container is maintained at a teml p'erature approximately at1nospheric, any freduction in pressure will tend to vaporize par-trot the chlorine and to reduce the tem- {p'erature of ,7 the unvaporized liquid chlorine to its vaporizing temperature under the preveiling conditions of temperature and ressure. When the liquid chlorine is passed through an expansion valve and its pressure reduced for example from around 80 lbs.

to around 5 lbs. or slightly above at'mos-.

temperature is lowered to that'approximat-' ing the boiling point of liquid chlorine at atmospheric or at the predetermined .pressure above atmospheric; and the liquid chlorine and vaporized chlorine can then be brought directly in contact with the solution to be chlorinated. With the liquid chlorine and the vaporized chlorine at such a low temperature, they will have a marked cooling effect upon the solution into which they are introduced and this cooling efiect will to a very large extent neutralize. the heat of reaction, as above ointed out.

Even where the liquid chlorine is not vaporized to any large extent before it is rought into contact with the solution to be chlorinated, yet where the solution is at a much lower pressure than that in the chlorine container, the temperature of the solution will ordinarily be much higher than the vaporizing temperature of the liquid chlorine at the lower temperature, and the liquid chlorine coming in contact with the solution to be chlorinated will tend to a greater or less extent to be vaporized, although some of the chlorine may be directly admixed with and combined with the solution without undergoing intermediate vaporization.

The apparatus of the invention may vary in its construction. In general, the liquid chlorine container will be directly connected with the container of the solution to be chlorinated so that the liquid chlorine can be di rectly discharged into the solution. It may thus be atomized in very fine streams directly into the solution, or it may be introduced through an injection nozzle or with a venturi effect, or it may be introduced into a vigorously agitated portion of the solution in which it will be rapidly disseminated.

One advantageous method of introducing the liquid chlorine into the solution is to cause circulation of the solution through a circulating line by means of a circulating pump or equivalent device andto introduce the liquid chlorine directly into the solution in the pump so that the pum will serve as an agitating means for. e ectively dis seminating and distributing the chlorine throughout the alkaline solution.

When a batch of milk of lime is to be treated, this may be circulated round and 'round through a circulating line by means of a pump which draws ofi the solution at one point and returns'it to the main body at another. In such. a circulating system, the chlorine can be directly introduced into the circulating line and intimately admixed with theicirculating liquor and in this way gradually introduced into the main body of the solution.

An improved apparatus embodying the mvention and adapted for the practice of the process of the invention is illustrated in a somewhat conventional and diagrammatic manner in the accompanying drawing in vertical section and with part in elevation.

In the apparatus illustrated, the mixing tank 1 has an inclined bottom and an outlet pipe 3 leadin to the suction side of a pump 4, which discharges through the pipes 5 and 6, back to the mixing tank through the outlet pipe 7. A separate outlet pipe 8 is provided, also connected to the suction side of the ump, and having a pipe section 9 pivoted t ereto in such a Way that the upper end of the permit rawing off of the clear settled chlorinated liquor from different levels. The discharge side of the pump is also connected through the pipes 5, 10 and 13 to the stock tank 14 from which the solution can be withdrawn through the pipe 15 "andpumped by the pump 16 through the pipe 17, to the place of use of the solution. A cleanout drain 18 is provided for the stock tank 14 and a similar drain pipe 19 is provided at the bottom of the mixing tank 1.

The liquid chlorine is supplied from the container 21 which may be a drum of, for example, 1 ton capacity, and is drawn off through the valve 22 at the bottom of the container so that the vaporization of the chlorine and drawing oii of gaseous chlorine from the to of the container is avoided. The liquid 0 lorine passes through the pipe 23, past the expansion'valve 24 where its pressure is reduced and then through the pipe 25 and discharging into this pipe just before the solutiontherein is admitted to the pump 4 in such a way as to promote the circulation by an injector action. The rate.

pipe 9 can be raised. or lowered to regulated properly, and with the flow of milk of lime solution regulated, the liquid chlorine will enter the circulatin stream and will be intimately admixed by t e pump aiid the chlorinated solution will then be dis-,

charged through the discharge line 6 back into the tank from which the milk of lime is withdrawn. The solution in the tank will thus be progressively chlorinated.

In the operation of the apparatus illus-' trated, the alkaline ,solution, for example,

milk of lime, is introduced into the mixing mixing tank through the suction pipe 3 and.

the chlorine gas escaping through the expansion valve 24 Will enter this stream and be drawn into the pump with it and the hquid chlorine and solution will be intimately admixed by the pump and the mixture will be discharged through the line 7 back to the tank 1. This circulation will be continued'untilthe alkaline solution has been chlorinated to the desired degree.

With a-rapidly rotating centrifugal pump, the chlorine introduced in liquid form, or partly in liquid form and partly asvaporized chlorine, will be subjected to.v1gorous agitation in the pump. The cooling ett'ect of the liquid chlorine will be exerted upon the solution with which it is admixed, and will to a considerable extent neutralize the heat of reaction between the chlorine and the milk of lime or other alkaline solution.

When the solution has been chlorinated -to the desired degree, as determined by test,

amount of milk of lime, the chlorine supply is cut off and the circulation of the pump is stopped, and. the solution is permitted to settle. to-free it from undissolved lime or other impurities which can be drawn off through the clean-off pipe 19. The clear settled chlorinatedliquor can be drawn ofi through the pipe 9, the upper end of which may be lowered for this purpose. In this case,'the valve in the pipe 3 and 6 will be closed and those in the pipe 8 and 10 open, and the clear solution will be pumped into the stock tank or storage tank 14 from which it can be withdrawn as-desired through the pipe 15 and 17.

It will thus be seen that the present invention makes use of the coblingeifect of the liquid chlorine, and utilizes the chlorine direct y while still in a liquid state, by in? troducmg it directly into the liquid or solu tion to be chlorinated, with thorough a tation of'the liquor and chlorine, or s ciently intimate dissemination of the chlorine throughout the. liquor, so that effective reaction and absorption of the chlorine by the solution takes place.

' The apparatus of the invention is of more or less eneral application to the produc-. tion ofb each solutions by chlorinating milk of lime or by chlorinating solutions of other alkaline substances. v

- I claim:

1. An apparatus for chlorinating solu tions comprising a tank or container for the solution, a circulating line for withdrawing solution from said tank and returning it thereto, a pump for circulating the solution through said circulating line, a container for liquid chlorine under pressure, a line for conducting chlorine directly into the cir-' culating-solution external of the tankand on the intake side of the pump and adjacent thereto whereby the chlorine is intimately admixed with the solution by means of the pump, and means in said chlorine conducting line for reducing the pressure of the liquid chlorine.

'2. An apparatus for chlorinating solutions comprising a'tank or container for the solution, a; circulating line for withdrawing solution from said tank and returning it thereto, a pump for circulating the solution through said circulating line, a container for liquid chlorine, an injector in the circulating line of the. solution external of the tank and on the intake side of the pump and adjacent thereto, and means for conducting liquid chlorine from the chlorine container to the injector.

3. An apparatus for chlorinating solutions comprising a tank or container for the solution, a circulating line for withdrawing solution from said tank and returning it thereto, a pump for circulating the solution through sald circulating line, a container for liquid chlorine, an injector in the circulating line ofthe solution external of the tank and on the intake side of the pump and adjacent thereto, means'for conducting liquid chlorine from the chlorine container to the injector. and means between the liquid chlorine container and the injector for reducing the pressure of the liquid chlorine.

4. An apparatus for chlorinating solutions tainer for liquid chlorine under pressure means for conducting liquid chlorine from the chlorine container and admitting it into the circulating line external of the tank and on the intake side of thepump and adjacent thereto and. means for reducing the pressure of the liquid chlorine before it is admitted into the c' culating line. 1

In test' ony whereof I aflix my si nature. JAMES H; MAGMAHON.- 

